Analysis of Intact Glucuronides and Sulfates of Serotonin, Dopamine, and Their Phase I Metabolites in Rat Brain Microdialysates by Liquid Chromatography−Tandem Mass Spectrometry
- 22 September 2009
- journal article
- research article
- Published by American Chemical Society (ACS) in Analytical Chemistry
- Vol. 81 (20), 8417-8425
- https://doi.org/10.1021/ac901320z
Abstract
A method for the analysis of intact glucuronides and sulfates of common neurotransmitters serotonin (5-HT) and dopamine (DA) as well as of 5-hydroxy-3-indoleacetic acid (5-HIAA), 3,4-dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) in rat brain microdialysates by liquid chromatography−tandem mass spectrometry (LC−MS/MS) was developed. Enzyme-assisted synthesis using rat liver microsomes as a biocatalyst was employed for the production of 5-HT-, 5-HIAA-, DOPAC-, and HVA-glucuronides for reference compounds. The sulfate conjugates were synthesized either chemically or enzymatically using a rat liver S9 fraction. The LC−MS/MS method was validated by determining the limits of detection and quantitation, linearity, and repeatability for the quantitative analysis of 5-HT and DA and their glucuronides, as well as of 5-HIAA, DOPAC, and HVA and their sulfate-conjugates. In this study, 5-HT-glucuronide was for the first time detected in rat brain. The concentration of 5-HT-glucuronide (1.0−1.7 nM) was up to 2.5 times higher than that of free 5-HT (0.4−2.1 nM) in rat brain microdialysates, whereas the concentration of DA-glucuronide (1.0−1.4 nM) was at the same level or lower than the free DA (1.2−2.4 nM). The acidic metabolites of neurotransmitters, 5-HIAA, HVA, and DOPAC, were found in free and sulfated form, whereas their glucuronidation was not observed.Keywords
This publication has 27 references indexed in Scilit:
- Discovery of Dopamine Glucuronide in Rat and Mouse Brain Microdialysis Samples Using Liquid Chromatography Tandem Mass SpectrometryAnalytical Chemistry, 2008
- Nomenclature update for the mammalian UDP glycosyltransferase (UGT) gene superfamilyPharmacogenetics and Genomics, 2005
- Human UDP-Glucuronosyltransferases: Metabolism, Expression, and DiseaseAnnual Review of Pharmacology and Toxicology, 2000
- Expression of UDP-Glucuronosyltransferases (UGTs) 2B7 and 1A6 in the Human Brain and Identification of 5-Hydroxytryptamine as a SubstrateArchives of Biochemistry and Biophysics, 1999
- Identification of the Uridine Diphosphate Glucuronosyltransferase Isoform UGT1A6 in Rat Brain and in Primary Cultures of Neurons and AstrocytesArchives of Biochemistry and Biophysics, 1998
- Sulfotransferase molecular biology: cDNAs and genesThe FASEB Journal, 1997
- Sulfate Conjugation of Dopamine in Rat Brain: Regional Distribution of Activity and Evidence for Neuronal LocalizationJournal of Neurochemistry, 1984
- Presence of Conjugated Catecholamines in Rat Brain: A New Method of Analysis of Catecholamine SulfatesJournal of Neurochemistry, 1981
- Determination of conjugated monoamine metabolites in brain tissueJournal of Neural Transmission, 1976
- Conjugated 3,4 dihydroxy phenyl acetic acid (DOPAC) in human and monkey cerebrospinal fluid and rat brain and the effects of probenecid treatmentLife Sciences, 1976